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The South China Sea Disputes: A Brief Introduction in International Law

Recent developments in the South China Sea implore us to examine the situation from both a legal perspective and an international relations perspective in order to understand these developments clearly. In that legal and political context, this article aims to examine the South China Sea as both a huge energy resource and a legal instrument that is subject to an international arbitration tribunal in the context of the dispute settlement procedure. Additionally, the article will contrast the arguments forwarded to international arbitration by both parties, and analyze them through the lens of the United Nations Convention on the Law of the Sea (UNCLOS), which regulates high seas, territorial waters, exclusive economic zones, etcetera. Thereafter, recent activities which are exacerbating the tensions in the South China Sea will be discussed briefly, as well as the legally binding verdict of the international arbitration tribunal.

Introduction to the South China Sea dispute: Energy resources

To understand the scope of the dispute in the South China Sea, we must first examine the importance of the energy resources that can be found in the seabed and subsoil. The South China Sea currently holds 11 billion barrels of oil, 190 trillion cubic feet of natural gas, and contains 10 percent of the fisheries of the world. Also, followed by the Dover Strait, 30 percent of the global shipping trade of the world flows through the South China Sea. These resources, combined with its estimated population of 2.2 billion, make the South China Sea area a big deal.

China is currently the largest offshore energy producer in the continent of Asia. With numbers, China’s offshore oil production is equal to fifteen percent of China’s aggregate oil production. That means offshore oil production constitutes a key point for coastal states whose Exclusive Economic Zones (EEZ’s) are in dispute due to the maritime delimitation problem. In recent years, China started to use oil and gas resources held in the South China Sea, mostly in the undisputed areas (Hong, 2013). However, China is not alone in sourcing oil and gas reserves in the South China Sea. Vietnam is also ambitious in its plans to explore and exploit energy resources. The Philippines is also interested in self-sufficient macroeconomic policies by refining offshore oil through foreign companies (Hong, 2013). The problem is that Vietnam and the Philippines are exploring and exploiting energy resources around in the disputed areas despite Chinese warnings. China claims most of the South China Sea as falling under their historic rights. In that context, China officially made its historical claim with the “nine-dash line” doctrine.

Chinese Controversial Historic Rights and the Nine-Dash Line

The notion of “historic rights” has played a key role in China's foreign policy approach to the South China Sea. Through this term, China claims sovereign rights in the South China Sea region: “China has indisputable sovereignty over the islands in the South China Sea and the adjacent waters, and enjoys sovereign rights and jurisdiction over the relevant waters as well as the seabed and subsoil thereof” (China’s note verbale to the UN Secretary-General, 2009).

The nine-dash line, then, indicates the limit of China’s sovereign rights over the South China Sea (Dupuy & Dupuy, 2013). In the map below, red lines indicate the nine-dash line.

According to the nine-dash line map, China’s EEZ covers other coastal states’ EEZ’s. By prevailing its sovereign rights over the other countries, China claims the territories in the region belong to them “historically”. However, the term “historic right” itself is widely controversial. To understand the historic rights, we need to differentiate it from “historic title”. The historic title is more about state possession and acquiring territory. Apart from the historic title, historic rights may contain limited sovereign rights over a territory (Dupuy & Dupuy, 2013). In terms of examining the historic title over the sea, the UN Secretariat established a guideline for a clear understanding of the concept. According to the “Juridical Regime of Historic Waters, Including Historic Bays”, there are three elements to be considered when determining historic title (Miyoshi, 2012):

  • the exercise of authority over the area by the State claiming the historic title;

  • the continuity of this exercise of authority;

  • the attitude of foreign States.

In order to gain validity under international law, all three must be taken into consideration to determine the region whether belonging in the scope of the historical title to a claiming state. However, the problem derives that UNCLOS does not recognize any sovereignty claimants over waters on the grounds of "historic rights", largely because the term discussed above itself is controversial and ambiguous (Dupuy & Dupuy, 2013). Meanwhile, China itself has been a party to the convention since 1996.

For that reason, the term of historic rights in international law indicates very limited legislation to prevent countries unilaterally claiming territory for themselves. Because of this limitation, several scholars stipulate that China has asserted only historic evidence rather than legal evidence to justify its territorial claims (Miyoshi, 2012).

International Arbitration Tribunal Between China v. Philippines

The Philippines, which was directly affected by the nine-dash line map that was unilaterally declared by China, searched for judicial remedies to invoke a reaction from the international community. Concordantly, the Philippines unilaterally invoked the international compulsory arbitration procedure in the scope of the UNCLOS Agreement. According to Article 287 and Annex VII of UNCLOS, such an action constitutes a legal argument that can be forwarded to the international arbitration tribunal as it fulfills the criteria of the Choice of Procedure section. China defended itself by asserting that the Philippines unilaterally asserted compulsory arbitration procedure despite China’s unwillingness to get involved in that arbitration. Furthermore, China asserts that recent disputes held in the South China Sea are irrelevant to the interpretation or application of UNCLOS, which the Philippines has disputed.

Despite China’s objections to involvement in the arbitration and China’s assertive policy that non-involvement will result in a non-binding award, the Philippines’ unilateral right to move to compulsory arbitration procedure is considered a legal remedy under the UNCLOS. The international arbitration tribunal gave a verdict claiming that China has no legal ground to stand on under international law, and that both parties are obliged to comply with UNCLOS.

Conclusion and Recent Developments

Despite the binding nature of the tribunal’s verdict, China seems to refrain from acting within the norms of international law and officially opposes the award of the tribunal. Also, China blamed the Philippines by demanding that it immediately stops its baseless allegations to avoid negative impacts on bilateral relations and peace and stability in the South China Sea (Xinhua, 2021). Furthermore, recent developments about fishing boats between China and the Philippines indicate the dispute in the South China Sea is more about future problems than present-day problems (BBC, 2021). In that context, the dispute in South China needs a broader approach by parties to a dispute within the principle of goodwill that the law assumes for all parties. China should review its objections and its claims within the legal framework rather than military remedies and aggressive unilateral policies.



Map credit: Goran tek-en, CC BY-SA 4.0 <>, via Wikimedia Commons

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BBC (2021, April 8). South China Sea dispute: Huge Chinese 'Fishing Fleet' Alarms Philippines. BBC News. Retrieved from:

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Xinhua. (2021, April 8). China urges Philippines to stop South China Sea allegations. Global Times. Retrieved from:

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